On 14 September 2008, a Robinson Helicopter Company R44 Raven helicopter, registered VH-RIO, was being operated on a series of scenic flights in the Bungle Bungle ranges area of the Purnululu National Park, which was about 250 km south of Kununurra, Western Australia. At about 1230 Western Standard Time, the helicopter departed the Purnululu Aircraft Landing Area for an 18- minute scenic flight with the pilot and three passengers. When the helicopter did not return by the nominated time, a search was initiated. Shortly after, the burnt wreckage of the helicopter was located. The four occupants were fatally injured.
The pilot had deviated from the regular scenic flight track, speed and profile to operate out of ground effect (OGE) in close proximity to the terrain at a low airspeed or at the hover. The helicopter's estimated OGE hover performance was marginal. It is likely that the high level of engine power required to sustain a hover in the local conditions was not available, or not fully utilised by the pilot, resulting in; an uncommanded descent, overpitching of the main rotor as a result of the pilot's attempts to arrest that descent, and a main rotor RPM decay that significantly increased the rate of descent.
As a result of the investigation into this occurrence, two minor safety issues were identified:
- There was no Australian requirement for endorsement and recurrent training conducted on Robinson Helicopter Company R22/R44 helicopters to specifically address the preconditions for, recognition of, or recovery from, low main rotor RPM.
- There was a lack of assurance that informal operator supervisory and experience-based policy, procedures and practices minimised the risk of pilots operating outside the individual pilot's level of competence.
In response, the aircraft operator has since formalised the operating parameters applicable to pilots conducting scenic flights. In addition, the Civil Aviation Safety Authority will be reviewing the training requirements affecting R22/44 helicopters. The Australian Transport Safety Bureau has issued a Safety Advisory Notice to encourage operators to address the risk of their pilots operating outside the individual pilot's level of competence.
Preliminary report released 31 October 2008
At about 1250 Western Standard Time on 14 September 2008, a Robinson Helicopter Company R44 Raven helicopter that was conducting a scenic flight of the Bungle Bungles impacted the ground 5 km north-east of the Purnululu Aircraft Landing Area (ALA), WA. The pilot and three passengers were fatally injured and the helicopter was seriously damaged.
RESPONSE TO BUNGLE BUNGLE INQUEST FINDINGS
A Western Australian Coroner recently released findings into a 2008 fatal Robinson R44 Raven helicopter accident near Purnululu in the Bungle Bungle Ranges in Western Australia. The findings highlight a number of safety concerns that require review by the aviation industry in relation the safety issues raised by the ATSB in its report released on 7 July 2010.
These issues cover:
- Recovery from Low Main Rotor RPM;
- Formalisation of Operator, Policies, Procedures and Practices
Circumstances of the accident
On 14 September 2008 a Robinson R44 Raven Helicopter, VH-RIO, crashed near Purnululu in the Bungle Bungle Ranges in Western Australia. All four occupants were fatally injured. The ATSB investigation advised that it was likely that due to the local conditions the helicopter was in a situation where the necessary engine power was either unavailable, or not fully utilised by the pilot, to sustain a hover. The crash site indicated there had been significant main rotor RPM decay and a high rate of descent.
The ATSB found the following safety issues as part of the investigation:
1. Recovery from Low Main Rotor RPM
There was no Australian requirement for endorsement and recurrent training conducted on Robinson Helicopter R22/R44 helicopters to specifically address preconditions for, recognition of, or recovery from, low main rotor RPM.
At the time of the release of the ATSB report, CASA had advised that it was reviewing the requirements for initial pilot training and endorsement and recurrent training on all helicopters, including a review of the Helicopter's Flight Instructor's Manual.
While noting that CASA was undertaking this review, the Coroner made a recommendation for CASA to address the safety issue raised by the ATSB.
In response to the safety issue CASA has advised the ATSB as follows:
"CASA is intending to produce an Instructor Pack for Awareness Training (AT) on the key hazards as specified in FAA SFAR 73. This AT would be generic in nature, but would address specific discussion points on matters relevant to specific types, including but not limited to R22/R44."
2. Operator policy, procedures and practices
During the course of the investigation the ATSB also considered it necessary to draw the attention of all operators in the industry to the potential lack of assurance that informal operator supervisory and experienced-based policy, procedures and practices minimise the risk of their pilots operating outside the individual pilot's level of competence.
Operators were encouraged to take action where considered appropriate.
The ATSB continues to advocate that all operators in the industry should consider their procedures for appropriately tasking pilots. Backing this, the Coroner noted the specific risks associated with low flight, including conducting aerial photography.
ATSB Investigations and Coronial Inquiries
Inquests are separate to ATSB investigations. In this matter the respective authorities largely agree on what the safety issues are that the industry needs to take account of.
The ATSB's report can be downloaded by clicking on the link: AO-2008-062. Feedback can be provided via the website.
The Coroner's report can be obtained from the Coroner's Court of Western Australia. Contact details are available at: http://www.coronerscourt.wa.gov.au. Queries regarding the Coroner's findings should be directed to the Coroner's Court of Western Australia.
|Date:||14 September 2008||Investigation status:||Completed|
|Time:||1246 WST||Investigation level:||Complex - click for an explanation of investigation levels|
|Location:||6 km NE Purnululu ALA|
|State:||Western Australia||Occurrence type:||Collision with terrain|
|Release date:||07 July 2010||Occurrence class:||Operational|
|Report status:||Final||Occurrence category:||Accident|
|Highest injury level:||Fatal|
|Aircraft manufacturer||Robinson Helicopter Co|
|Type of operation||Charter|
|Damage to aircraft||Serious|
|Departure point||Purnululu ALA|
|Departure time||1230 WST|